My bow is shooting bullet holes through paper with field points. When I screw on my broadheads, they take a nose dive once I get to 30 yards. They fly straight and go straight into the target at 20 yards, but past that, its nearly impossible to judge where they will go. What could be wrong? Thanks.

Are they the same weight as your field points?

yes, 100 grains. Could a weak spine possibly cause this?

Are you broadheads spin tested? If not then i would recommend taking them to get spin tested...I do this with all of my broadheads...If you wanna try something real quick cause you dont have time to get them spin tested....Make sure that the blades line up with the fletching and its good to have at least 4" fletching but if you don' t thts ok...Take one of your arrows with a broadhead in it and heat up the insert, spin it 4 complete rotations and line it the blades up with the vains....What the rotating does is spreads the insert glue evenlly, because if you have a glob it on one side of the insert then that side may be affecting flight...But if that dont work then let me know and ill think of something else

Possibly shooting form, less than perfectly seated insert, or underspined arrow...?

Thanks guys, I fixed the problem. it was a SLIGHTLY underspined arrow. I put 2 more silensers on the string and back the draw ewight off a half turn and they are shooting great now

give us a pic whenever you get the first passthrough on the deer